In present study, the effects of optimization on seismic energy spectra including input energy, damping energy and yielding hysteretic energy are parametrically discussed. To this end, 12 generic steel moment-resisting frames having fundamental periods ranging from 0.3 to 3s are optimized by using uniform damage and deformation approaches subjected to a series of 40 non-pule strong ground motio...

Most of the existing seismic design codes are based on the empirical knowledge accumulated through systematic earthquake damage data collection and their analysis. Required levels of protection and seismic design forces gradually are increased after each series of catastrophic earthquakes particularly in developed countries. Many efforts have been made through experimental and analytical studie...

The main aim of this study, is to evaluate the seismic reliability of steel concentrically braced frame (SCBF) structures optimally designed in the context of performance-based design. The Monte Carlo simulation (MCS) method and neural network (NN) techniques were utilized to conduct the reliability analysis of the optimally designed SCBFs. Multi-layer perceptron (MLP) trained by back propagati...

The influence of the near-fault ground motion on the response of long-span bridges must be considered as a critical factor for seismic design because the response indicates different aspects from existing earthquake characteristics. Also, it is important to note that the safety index for the risk assessment of long-span bridges is determined based on the minimum expected lifecycle cost E(LCC). ...

In this paper a simple tool for seismic design of steel structures for a selected ductility level is presented. For this purpose, a consistent set of earthquakes is selected and sorted based on the maximum acceleration of ground surface. The selected records are applied as the base motion to a single-degree-of-freedom system with strain hardening and the maximum response acceleration is determi...

The earthquake engineering community recognizes the need to improve current seismic codes and design methods in the light of recent inadequate behavior of building structures. Presently, the performance-based earthquake engineering is being envisioned as the solution to this problem. In this new design approach, the desired behavior of the building is formulated first in the conceptual stage fo...

Within the past decade, seismic isolation systems have gained rapid popularity in the earthquake resistant design of bridge structures. This popularity has come in response to the inadequacy of earlier seismic design and retrofit methodologies. The mechanical shortcomings and subsequent failure mechanisms associated with the early elastic seismic design philosophy are first presented, followed ...

It is known that the seismic response of a structural system is highly influenced, in addition to the earthquake input, by the dynamic characteristics of the system itself. This paper presents an approach for the identification of the characteristics of the structural system resisting to horizontal loads which enables to satisfy given seismic performance objectives. This is achieved by consider...

In seismic resistance design, the design seismic motion is usually defined by elastic response spectra to reflect the characteristic in frequency. Whilst, either the phase of a reference seismic record or random phase is used in generation of artificial wave. The influence of phase on structural response can not be properly defined, as it is often omitted for linear elastic responses. But for t...

The main purpose of this paper was to use a combination of Energy-based design method and whale algorithm (WOA), hereinafter referred to as E-WOA, to optimize steel moment frames and improve the seismic performance. In E-WOA, by properly estimating the seismic input energy and determining the optimal mechanism for the structure, steel frames are designed based on the energy balance method; acco...